Pier-and-Beam Problems in Older DFW Neighborhoods

Drive through East Dallas, Oak Cliff, the older parts of Fort Worth, or the historic blocks around downtown Garland, McKinney and Wylie, and you will see a lot of houses sitting a couple of feet off the ground. Those are pier-and-beam homes. Instead of resting on a concrete slab, the floor is framed with wood beams and joists that sit on piers, with a crawl space underneath.

Pier-and-beam construction has real advantages. You can get under the house to reach plumbing and wiring, and the floor can be re-leveled without breaking concrete. But many of these homes are 60 to 100 years old, and time, Texas clay and Texas humidity have been working on them the whole time. Here is what usually goes wrong and how it gets fixed.

How a pier-and-beam foundation carries your house

Understanding the parts makes the problems easier to spot:

• Piers: concrete, masonry or, in very old homes, wood or cedar posts set into the ground. They carry the weight down to the soil.
• Beams (girders): heavy timbers that run across the piers.
• Sill plates: the wood that sits on the perimeter foundation wall or grade beam.
• Joists: the smaller framing members that span between beams and carry the subfloor.

Every one of those parts can fail, and a problem in one usually shows up as a floor problem somewhere above it.

Sagging and bouncy floors

This is the most common complaint. You walk across the living room and the china cabinet rattles, or there is a noticeable dip in the hallway. The usual causes are:

• A pier that has settled or tilted. The expansive clay across North Texas moves with the seasons, and a pier sitting on shallow soil moves with it. When a pier drops, the beam above it loses contact and the floor sags. We explain the clay cycle in Why DFW Homes Crack.
• Piers spaced too far apart. Older homes were often built with long spans between supports. Decades of load make the beams and joists deflect.
• Undersized or damaged joists. Joists that were notched for plumbing or ductwork, split, or eaten by insects lose stiffness.
• Old shims that have crushed or rotted. Many older homes were leveled with wood shims stacked on top of piers. Wood compresses and decays, and the floor slowly drops again.

Rotted sill plates and beams

Rot is the problem people do not see until they go under the house. Wood that stays damp for long enough grows fungus and loses strength. The sill plate on the perimeter is especially exposed because it sits closest to the outside soil, and it catches any water that gets past the siding or flows toward the house from poor grading.

Signs of rot include wood that is soft when you press a screwdriver into it, dark staining, crumbling edges and a musty smell. A rotted sill can let the exterior wall settle, which shows up as cracks at windows, doors that bind and gaps between the wall and floor. Termites add to the damage in a lot of older homes, and the two problems often appear together because both are drawn to damp wood.

Crawl-space moisture from Texas humidity

North Texas summers are hot and humid, and a crawl space is a great place for that moisture to collect. Warm, wet outside air comes through the vents and meets the cooler ground and the air-conditioned floor above. Moisture condenses on the wood and ductwork. Add a yard that drains toward the house and you can end up with standing water under the floor after every storm.

Look for:

• Standing water or mud in the crawl space after rain
• Condensation dripping from ductwork or pipes
• Mold or mildew on joists and the underside of the subfloor
• Rusted nails and fasteners
• Cupped hardwood floors, which often come from moisture below

Controlling crawl-space moisture usually starts outside. The ground should slope away from the house, and gutters should discharge well away from the foundation. Inside the crawl space, a vapor barrier over the soil keeps ground moisture from evaporating into the space. Proper ventilation or a sealed crawl-space design handles the humidity. Our drainage and water management work often goes hand in hand with pier-and-beam repair for this reason.

Shimming vs. adding new piers

This is where a lot of homeowners get different answers from different contractors, so it is worth understanding the difference.

Shims are not a bad repair. They are the right tool when the problem is small and the structure underneath is healthy. The trouble starts when shims are used to hide a pier that keeps moving or wood that is rotting. The floor looks better for a season and then drops again. If your house has been shimmed several times, that pattern is a sign the real cause has not been addressed.

What a proper evaluation looks like

For a pier-and-beam home, we take floor elevation readings throughout the house to map the high and low points, then go into the crawl space. We check every pier we can reach for tilt, cracking and contact with the beam, probe the sills and beams for rot, look at joist spans and condition, and note moisture, standing water and ventilation. The outside walk covers grading and gutters, because water is usually part of the story.

You get the findings documented, with the readings and what we saw under the house. That way you can see why a particular pier needs replacing, where new supports go, and which framing needs repair, instead of taking a number on faith. For background on how we approach any foundation evaluation, read Understanding Foundation Repair.

Older homes, historic districts and renovations

Many of the pier-and-beam homes we see are in established or historic neighborhoods, and a lot of them are in the middle of a renovation. That is a good time to deal with the foundation. Re-leveling after new floors, cabinets and drywall go in can crack the new finishes. If you are planning a remodel in an older Dallas, Fort Worth, Garland, McKinney or Wylie home, get the foundation evaluated first, then do the structural work, then the finishes.

Once the structure is stable, our paint and sheetrock crew can repair the cracks that the movement left behind, so the fix is complete from the crawl space to the ceiling.

When to call

Call if your floors have become noticeably bouncier or more sloped, if doors that used to close now stick, if you see water or mold in the crawl space, or if the house has been shimmed before and the problem came back. Texas Structural Concepts repairs pier-and-beam and slab foundations for homes and commercial buildings across Dallas-Fort Worth. Learn more about our foundation repair service or schedule a free evaluation.